Machine for grinding balls and rollers.



G. WEEKSA MACHINE FOR GRINDiNG BALLS AND ROLLERS.

v APPLICATION FILED NOV. 28, 1914. M

LE 1H9 Patented Dec. 28, 1915.

2 SHEETS-SHEET i.

/N VEN T R 6. WEEKS.

MACHINE FOR GRINDING BALLS AND ROLLERS.

APPLICATION FILED NOV. 28, I914. 1,16 2%? Patented Dec. 28, 1915.

2 SHEETS-SHEET 2.

//v VEN TOR invites sorta PAENT enrich GEORGE WEEKS, OF CHELMSFSRD, ENGLAND, ASSIGNOR TO' THE HOFFMANN MANU- EACTUIRING COMPANY LIMITED, OF CHELMSFORD, ENGLAND.

MACHINE FOR GRINDING BALLS AND ROLLERS.

1 Specification of Letters Patent.

Patented Dec. 2%, 1915.

7 subject of His Majesty the King of Great Britain and Ireland, residing at Ghelms ford, Essex, England, have invented a new and useful Improvement in Machines for Grinding Balls and Rollers, of which the following is a specification.

This invention relates to machines for grinding balls, rollers, and the like, and particularly to that class of ball grinding machines in which the balls are ground between grooves located respectively in a rotating abrading disk and a cast iron or like disk, the two being capable of being opened out or closed together against spring pressure by a screw and hand wheel. In practice at present the two disks are tightened at intervals during grinding by the hand wheel to exert an increasing pressure upon the balls or the like being ground.

The object of the invention is to facilitate the action of the machine by rendering it automatiein respect of the operation of adjustment of the grinding pressure.

According to the invention means are employed for efiecting the increasing pres sure either regularly, or in increasing amount as the grinding progresses, so that in the latter case the first pressure maybe light to save the abrading disk and later or subsequent pressures heavier, with the result that both a saving of the grinding surface and of labor is effected. This is effected, for example, by causing a cam or moving portion of the machine to operate the hand wheel, or a nut substituted therefor, upon the usual screw shaft.

Other features such as the varyingrof the pressure and forming part of the invention will be referred to hereinafter.

In the accompanying drawings is shown a machine to illustrate an embodiment of the invention.

In these drawings :'Figure 1 is a side elevation of a known. form of ball grinding machine with the invention applied thereto: Fig. 2 is an end view of same looking in the direction of the arrow 00, Fig. I: Fig. 3 is a detail of some parts looking in the direction of the arrow y, Fig. 1, and Fi g. l is a partial end view of Fig. 1 looking in the direction oharrow e.

T he machine shown. comprises the usual non-rotatable disk 1 ofcast iron or other suitable material which is attached to a slidable hollow shaft 2 carried in a bearing 2 on the standard 3 and capable of being forced against a rotatable disk 7 by means of a nut 6 on a screwed shaft 4c which shaft is attached at its other end to a shaft 8. Tothe nut 6 is attached the spur wheel 5 which in this case replaces the usual hand wheel. The rotatable disk 7 is usually of abrasive material and rotates on the stationary shaft 8 clamped in a bearing 9 of a. standard 10, the disk 7 being slidable on its shaft against the pressure of a spring 11 and carrying for rotation purposes a spur wheel 12 driven. from a. pinion 13 on a shaft 14 carried in a bearing 15 through a pulley 16, the above being, with the exception referred to, all known mechanism.

For the purposes of the invention the usual casing 17 of the rotating disk 7 carries a cam 18 in contact with a roller 19 fixed on the end of a rocking arm 20, attached to a shaft 21, supported in bearings 22, which shaft 21 has attached to it at the opposite end a lever 23,, which in turn carries a roller 24 adjustable by its stud and nut 25 in a slot 26 of the lever, the roller 24; being thus capable of movement in a slot 27 of an arm 28 pivoted on the end of a shaft 29 supported in a bearing 29 Onthe opposite end to the slot of arm 28 is a pawl 30 pi oted to the arm on a pin 31, which pawl engages a ratchet wheel 32 rotatable on the shaft 29, said wheel being fast to a gear 33 so that the latter can communicate motion to gears 34L, 35, fast on a stub shaft 36 supported in a bearing 37 which transmit motion to a gear wheel 38 fast on shaft 29, the latter carrying a pinion 39 engaging spur wheel attached to the nut 6, by the rev0lution of which, through the action of the pawl 30, pressure is exerted on the fixed androtatable disks against the spring 8. 3

Adjustment of the amount of feed can be effected by altering the travel of the pawl 30. ,This can be done by altering the position of the roller 2i on the le :er "23, its outward movement lengthening the effect of lever 23 and shortening the lower end of pawl. I roller shortens the travel of the pawl.

' i The spyjng 8 has an arm l0 attached to it (shown as placed between it and the wheel 12) which carries a finger ll acting upon the short end 42 of a pivotally mounted crank shaped pointer 43 which traverses a arm 28, the operation being that when the desired maximum pressure is reached and the pointer 43 contacts with a pin L5 on the pointer 45 and the circuit is closed, the core of the solenoid is lifted and the pin 54in consequence lifts the pawl out of engagement with the ratchet wheel 32, thus stopping the feed.

The increasing pressure, or an automatic variation or acceleration of the feed may be obtained for example, by providing the rocking arm 20 with a stepped stop 56 of say three diameters 56, 56 56, as shown, which is carried on. a rod 57 connecting the arm 20 with lever 23. This stop is adapted first to come into contact by its diameter 56 with a projection 58 (Fig. on the stationary disk 1, and thus arrests the complete throw or travel of the arm 20 so that the roller 19 is not allowed contact with the smallest diameter of the cam 18. As the disk 1 moves to the right during the compression of spring 11 and the pressure may be allowed to more rapidly increase in view of the increasing 'sphericity of the balls, the smaller diameter56 of the stop 56 will come into contact with. the projection 58 thus allowing of a greater stroke or travel of the arm 20. When the projection 58 has moved sufficiently to the right to allow the smallest diameter 56 ofthe stop to come into contact with it, then the roller 19 willbe resting on the smallest diameter of the cam and the maximum acceleration of the feed will be obtained. The arrangement may be for example that the diameter 56* allows motion of the pawl 30 over one tooth of the ratchet wheel, the diameter 56* over two teeth and the diameter 56 over three teeth.

The construction above described may be considerably modified in its details withoutdeparting from the spirit of the invention.

What I claim is 1.. In a machine for grinding balls, rollers, and the like, and in combination two opposed grinding bodies, between surfaces of which the articles are ground, means for exerting a normai 6 inding pressure between such surfaces, and means automatically operated, (Jo-acting with the first pressure means for varying such grindin pressure during the progress of the grlndlng operation.

2. In a machine for grlndlng balls, rollers, and the like and in combination, two 0pposed grinding bodies, between surfaces of which the articles are ground, means for exerting a normal grinding pressure between such surfaces and means automatically operated co-acting with the first pressure means for increasing the grinding pressure between such surfaces, lightly in an earl sta e of the rindin and to a reater b D7 P) extent in a subsequent stage.

- ers, and the like, and in combination, two

opposed grinding disks, means for carrying same, means, for pressing the surfaces of such disks together, a screwed shaft, a nut on same, a ratchet and pawl, means for operating the pawl with a step by step movement, and connecting means between the ratchet and the nut adapted to turn the shaft.

5. In a machine for grinding balls, rollers, and the like, and in combination, two opposed grinding disks, means for carrying same, means for rotating one of them, a spring for pressing the surfaces of:such disks together, a cam'operated by the rotating means, and connections between the cam and one of the disks for imparting a step by step,increase of pressure on the spring.

6. In a machine for grinding balls, rollers, and the like, and in combination, two opposed grinding disks, a slidable shaft carrymg one of same, a spring for pressing the surfaces of such disks together, means for rotating one of the disks, a cam carried by the rotating disk, rocking means operated by such cam, a pawl operated by the rocking means, a ratchet wheel operated by the pawl, and means operated by the ratchet wheel for imparting movement to the slidable shaft.

7. In a machine for grinding balls, rollers, and the like, and in combinatiorn'two opposed grinding bodies, a slidable shaft carrying one of same, means for pressing the surfaces of such disks together and thereby sliding one of same, means for rotating one of the disks, a cam operated by the rotating means, a ratchet and pawl mechanism operated by such cam and means controlling the action of such cam for gradually increasing the travel of the pawl upon its ratchet wheel.

8. In a machine for grinding balls, rollopposed grinding carried by the latter,

1,1eo,ase

grinding pressure between such surfaces. and means also automatically, operated for stopping the action of the ratchet and pawl ers, and the like, and in combination two disks, means for carrying same, means for ressing the surfaces of such disks together y slidably moving same, means for rotating one of such disk'as, a earn a rocking part on which the camlcan act,'a ratchet and pawl mechanism the pawl of which is operated by the rocking part, and means for delaying the full action of such cam upon the pawl for a certain period of the travel of the slidable disks.

9. In a machine for grinding balls, r0llers, and the like, and in combination, two opposed grinding bodies, between surfaces of which the artlcles are ground, means for exerting a grinding pressure between such surfaces, means automatically operated. for increasing such. grinding pressure during the progress of the grinding operation, and means also automatically operated for terminating such increasing pressure.

10. In a machine for grinding balls, rollpressure.

11. In a machine for grinding balls, rollers, and the like, and in combination two opposed grinding disks, means for rotating one of same, means for carrying both, means for slidably moving one of same, means for pressing such disks together, means automatically operated comprising a ratchet and pawl mechanism for increasing the grindtric circuit means included in such circuit for acting upon the pawl and contact means also included in such circuit connected to the slidable movable disk whereby the circuit may be complete at a point in the movement of such disk caused by the increasing pressure.

In witness whereof I have hereunto set my hand in the presence of two subscribing ers, and the like, and in combination, two, witnesses. opposed grinding bodies between surfaces GEORGE WEEKS. of which thearticle's are ground, means au- Witnesses:

tomatically operated comprising a ratchet WILLIAM HOLMES, and pawl mechanism for increasing the LIONEL AUBREY LEE.

mechanism and terminating such increasing ing pressure between such surfaces, an elec- 

